Since these isolators are only used at the abutments, and monolithic or pinned connections remain at the piers, the technique is called hybrid isolation.
The objectives of this methodology are: 1) keep the column essentially elastic; 2) reduce the displacement demand of superstructure; and 3) minimize the pounding between the deck and the abutment. This technique is applicable to a wide range of bridges including those not suitable for full isolation, such as a bridge with a continuous superstructure that is monolithic with its piers. The application of hybrid isolation is suitable for both new bridges and retrofit work.
a series of shake table testings of a 2/5th, a three-span curved bridge model were conducted to investigate the response of bridges with hybrid isolation, and quantify the advantages and disadvantages of this approach in Large-Scale Structures laboratory at University of Nevada Reno.